1. Technical Field
The present disclosure relates to a coolant passage connection structure and a cooler system including a first connection member connected to a first coolant passage which extends from a cooler housed in a case, and a second connection member which is connected to the first connection member and also connected to a second opening of the case. The second opening communicates with a second coolant passage, via a face seal member.
2. Description of Related Art
Japanese Patent Application Publication No. 2014-102017 discloses an inverter to be installed in a vehicle. The inverter includes a first casing, a coolant passage (e.g. second coolant passage), an opening (e.g. second opening) that communicates with the coolant passage, and a second casing fixed to a bottom face of the first casing. The first casing houses a stacked cooling unit integrated with a plurality of power cards each housing a switching element (e.g. semiconductor element). A first connection tube (e.g. bush) is inserted through a through-hole formed in the first casing of the inverter, and the first connection tube is connected to a rigid tube (e.g. first coolant passage) extending from the stacked cooling unit, via a shaft seal member. Also, a face seal member is disposed between a flange of the first connection tube and the first casing. The flange of the first connection tube is fixed to the first casing via a bolt. Also, in the first casing, an opening (e.g. first opening) is defined by an end portion, on the side opposite to the rigid tube, of the through-hole (e.g. coolant flow hole) of the first connection tube. Furthermore, an end of a U-shaped second connection tube fixed to the second casing via a bolt is connected to the opening (e.g. first opening) of the first casing, the opening being defined by the bush, via a shaft seal member, and another end of the second connection tube is connected to the opening (e.g. second opening) of the second casing via a face seal member. A cooling medium is supplied from a coolant pump disposed outside the first casing to a coolant inlet of the stacked cooling unit. The cooling medium flowing through the stacked cooling unit takes heat from the power cards and a temperature of the cooling medium thereby increases, and the cooling medium flows into the coolant passage in the second casing via the rigid tube, and the first and second connection tubes. The cooling medium flowing through the coolant passage in the second casing takes heat from the first casing and the temperature of the cooling medium thereby increases, and the cooling medium flows into a radiator disposed outside the second casing.